Sodium maleate peroxyhydrate

ABSTRACT

Sodium maleate peroxyhydrate, useful as a combined detergent builder and bleach, is described, together with its preparation.

nited States Patent [15] 3,691,139 Blumbergs et al. [451 Sept. 12, 1972 SODIUM MALEATE [56] References Cited PEROXYHYDRATE UNITED STATES PATENTS [72] Inventors: John H. Blumbergs, Highland Park;

p Mucenieks, Trenton, both of 3,496,150 2/1970 Kropp ..260/78.4 NJ. Primary ExaminerJoseph L. Schofer [731 Asslgnee= FMC m i New York Assistant Examiner-John Kight, III

Attorney-Milton Zucker, Frank lanno, Eugene G. [22] Fil d; J 1 1970 Seems and Pauline Newman [21] Appl. No.: 47,551 [57] ABSTRACT I Sodium maleate pero xyhydrate, useful as a combined [52] "260/784 252/94 260/785 T detergent builder and bleach, is described, together [51] [11. Cl. ..C08f 27/04 with its preparation [58] Field of Search ..260/78.4 R, 78.5 T

2 Claims, No Drawings mulations.

1f. SODIUM MALEATE PEROXYHYDRATE BACKGROUND OF THE INVENTION The commonly used detergentcompositions include soapsand synthetic detergents, mixed with compounds known as builders, which act both to improvethe detergent power of the primary detergents, and to reduce the cost of the overall compositions. The inorganic .polyphosphates, such as sodium? and potassium tripolyphosphate, have been almost universally used asphosphates, is; both more expensive and potentially dangerous,' -in that-it. can keep quantities of'heavy 3,359,246 oras described in the copending Blumbergs et al. application titled "Preparation of sodium polymaleate, mailed to the Patent Office on May 28, I970 nowULS. Pat. No. 3,637,609. The product is a homopolymer with the structure Edith...

H- -CONu where n is at least 3, andmay be as high as is permitted by solubility consideration, generally not above about 500; most advantageously, the molecular weight is in the 2,500 to 25,000 range. The product dissolves readimetals in solution in. water. Other available buildersare either much-more costly,- or. have other serious drawbacks. I

A potentially interesting group of possible detergent builderscomprises the alkali metal salts of poly(carly in hot water when'in atypical built detergent, but so slowly in'cold water thati'it is'not useful in cold-water laundering. Moreover,'there is a tendency-to cause caking-'insomemixed detergent formulations. These disadvantages are overcome. by forming the-hydrate in which a mol of water is boundto each sodium atom.

We have found that the water in suchfla hydrate can be partially or completely replacedby hydrogen peroxide .without losing. the advantages, of the hydrated product over the anhydrous product, while at the same boxylic acid)s as described in Diehl'U .S. Pat. No.

3,308,067 issued Mar. 7, 1967. This patent describes the. use, as builders, of the water-soluble salts of poly(carboxylic acid )s, the simplest and least expensive of which are the sodium salts of various poly(maleic acid)s. The least expensive of these salts is sodium polymaleate; It has not, however, come into commercial use because of its slow solubility in cold water, and because it tends to cause caking inmixed detergent for- In copending application of Blumbergs and MacKellar, titled Sodium polymaleate hydrate," filed simultaneously herewith, therev is described a hydrate of sodium polymaleate with a mol of water for each sodium atom in the polymer, which is both more rapidly soluble in cold water and which does not cause caking in mixed detergent formulations.

STATEMENT OF THE INVENTION liquid carrier, and exposing it to hydrogen peroxide,.

preferably aqueous, to get the desired product, and filtering and drying the peroxyhydrate. The product is as rapidly soluble and as noncaking as sodium polymaleate hydrate, and is also useful in contributing bleaching power to a mixed detergent.

DETAILED DESCRIPTION OF THE INVENTION Sodium polymaleate, useful as a detergent builder, may be prepared as described in Berry US. Pat. No.

time adding to the product active oxygen which is a useful bleach in detergent formulations.

By using I00 percent hydrogen peroxide and anhydrous sodium polymaleate as the starting compositions, a product can be obtained with 29.8 percent of H 0, (14 percent active oxygen), corresponding to a mol of'H O per atom of sodium. However, the high cost of 100 percent hydrogen peroxide, and the dangers inherent in handling it, make this product economically undesirable. Material containing equal molar percentages of water and peroxide is much easier and more economical to prepare, and contains enough active oxygen (7.8 percent) to serve the purpose of adding a powerful'bleach to a mixed detergent composition-. We may, of course, operate over the-whole range of peroxide-to-water ratios,- and still get some bleaching value. I a

The method we use to prepare our new peroxyhydrates is to suspend the sodium polymaleate in a liquid medium which is a nonsolvent for the sodium polymaleate and is inert to the hydrogen peroxide, slowly add the hydrogen peroxide and water in the desired ratio, while agitating, to form the peroxyhydrate, and then filter the peroxyhydrate from the medium.

The sodium polymaleate used should preferably be anhydrous, but water can be compensated for by using more hydrogen peroxide or a more concentrated solution. The hydrogen peroxide may be employed in any desired concentration, depending on the ratio of peroxide wanted in the peroxyhydrate; it will add on in the same ratio as present in the reaction medium.

The reaction temperatures are a matter of choice; high temperatures favor fast reaction and peroxide decomposition, low temperatures slow the reaction. We prefer to operate at 30C. or lower for economic reasons, and for the same reasons prefer not to refrigerate.

Reaction times depend on temperature and agitation rates. Generally about 30 minutes are required for addition, and at ordinary ambient temperatures 1 hour overall is sufficient to ensure complete reaction.

The reaction medium can be any volatile liquid which is a nonsolvent for the polymer salt, and does not react with hydrogen peroxide under conditions of use. Ability to azeotrope excess water is useful. The carriers of choice are aliphatic, aromatic or alicyclic hydrocarbons and halogenated hydrocarbons boiling between 40 and 120C, e.g., chloroform, carbon tetrachloride, methylene chloride, the various perfluorocarbons, benzene, toluene, cyclohexane and petroleum distillates. These liquids all can be easily separated from the insoluble peroxyhydrates, and the small amounts adhering can be readily evaporated.

SPECIFIC EXAMPLES OF THE INVENTION The following examples of the invention are given by way of illustration, and not by way of limitation.

EXAMPLE 1 In a 250 ml beaker were placed 16 g of sodium polymaleate powder, l mesh, and 50 ml of toluene. A magnetic stirrer was used to stir the slurry, while 5.3 g of 70 percent hydrogen peroxide were added drop wise. Some lump formation was observed. The lumps were crushed and addition of H 0 continued. Total addition time was 35 minutes. The slurry was left overnight, then filtered and dried in a circulating air at 55C. There were obtained 16.9 g of white solids having an active oxygen content of 5.35 percent by weight.

EXAMPLE 2 The same as Example 1, only 50 ml of chloroform were used in place of toluene. There were obtained 17.2 g of white solids, having an active oxygen content of 6.35 percent.

EXAMPLE 3 The same as Example 1, only 50 ml of n-heptane were used in place of toluene. There were obtained 17.0 g of white solids having an active oxygen content of 6.12 percent.

EXAMPLE 4 The same as Example 1, only 50 ml of cyclohexane were used in place of toluene. There were obtained 17.3 g of white solids having an active oxygen content of 5.75 percent.

EXAMPLE 5 Sodium polymaleate, 80 g (0.5 mol), was placed in a 1-liter, three-neck round-bottom flask, supplied with a laboratory stirrer, condenser and Dean-Stark trap for collecting water. The flask was charged with 500 ml of toluene, which was boiled for 3 hours-under a slight reflux to remove all the moisture from the sodium polymaleate sample.

The flask content was then cooled to 10C in an ice bath and 27.0 g (0.55 mol) of 70% B 0 were slowly added with good stirring. Addition time was minutes. The slurry was then stirred for an additional hour, wa filtered and the solids were dried on Rinco under re uced pressure to remove the toluene solvent.

There were obtained 102 g of white solids, having an active oxygen content of 8.3 percent as determined by iodometric titrations.

EXAMPLE 6 The sodium polymaleate perhydrate samples were placed in glass jars with vented caps and were stored at 55C for 3 days to check the stability of this compound.

The active oxygen content was measured before and after the storage. The data are listed in Table l TABLE 1 Storage Stability of Sodium Polymaleate Perhydrate The data indicate that the sodium polymaleate perhydrate compound has sufficient storage stability to be used as a detergent builder and a bleach. Under the above mentioned accelerated test conditions, only a slight drop in active oxygen content was noticed.

Obviously, the examples can be multiplied indefinitely without departing from the invention as defined in the claims.

We claim:

1. Solid, noncaking sodium polymaleate peroxyhydrate containing one mol of hydrogen peroxide plus water of crystallization for each atom of sodium in the polymaleate.

2. The method of making solid non-caking sodium polymaleate peroxyhydrate containing 1 mol of hydrogen peroxide plus water of crystallization for each atom of sodium in the polymaleate, which comprises heating sodium polymaleate which is at least partially anhydrous suspended in a liquid nonsolvent therefor which .is nonreactive with hydrogen, with hydrogen peroxide in sufiicient quantity to yield a mol of hydrogen peroxide plus water per atom of sodium in the polymaleate for a sufficient time to complete pickup of the hydrogen peroxide by the sodium polymaleate, and separating the peroxyhydrate from the carrier. 

2. The method of making solid non-caking sodium polymaleate peroxyhydrate containing 1 mol of hydrogen peroxide plus water of crystallization for each atom of sodium in the polymaleate, which comprises heating sodium polymaleate which is at least partially anhydrous suspended in a liquid nonsolvent therefor which is nonreactive with hydrogen, with hydrogen peroxide in sufficient quantity to yield a mol of hydrogen peroxide plus water per atom of sodium in the polymaleate for a sufficient time to complete pick-up of the hydrogen peroxide bY the sodium polymaleate, and separating the peroxyhydrate from the carrier. 